Make Haste SlowlyBy Dale Willis One of my favorite driving instructors, Caesar Augustus (Roman Emperor, 63 B.C.-A.D.14) said it best – or at least first: “Make haste slowly.” Probably was talking about chariot racing. Today’s version of that same quote is: “Slow down to go fast.” At first blush that sounds contradictory, but you will learn that it is not. In this article, designed for novice drivers or as a non-technical refresher for others, I’ll overview (and perhaps oversimplify) a few car control concepts and techniques you need to understand and apply to begin developing the car weight control, balance and smoothness that will reduce your track times. As Dean Lewellen pointed out in Going Places a while ago, all of the control of your car comes through the four “contact patches” where your tires meet the road surface. Running the best tires you can afford for the purpose (not necessarily the most expensive) is important. Just notice that the drivers at the head of the autocross top time list are using racing tires. That doesn’t mean that you can’t have fun on street tires and occasionally do better than a driver sporting Yokohama’s or Kuhmo’s; but, to avoid too much frustration you need to compare your times against like-equipped cars. Second on the improvement list after tires are suspension upgrades such as stiffer sway bars and an after market Camber Truss. Note how the faster cars run “flatter” with less body sway. When you think about it, all suspension improvements are for the specific purpose of keeping the contact patches aligned with and on the racing surface as much as possible. Sway bars control the movement of the car’s body over the suspension system limiting the amount of weight shift during cornering. This makes the car more stable by reducing the unpredictability of body sway and better controlling or balancing the weighting on the tire contact patches. (I said I was going to oversimplify!) A Camber Truss (you’ll find it in the front trunk of a 911 or engine compartment of a 944) bridges the front suspension towers and keeps the front bodywork from flexing too much. Flexing is bad because it unpredictably changes the way the tires meet the road surface (camber) under differing loads. A Camber Truss gives the front end a more solid, stable feel, although its contribution to handling performance is probably minimal. Looks cool, though. Shock absorbers dampen the vertical movement of the wheel and tire on bumpy and uneven road surfaces keeping the contact patches on the road surface as much as possible. As high performance automobiles, Porsches are equipped with excellent shock absorber systems, which are quite effective for all but the highest performance racing needs. I still have the original Bilsteins on my ’81 SC and they are quite serviceable at 91,000 miles including lots of track and autocross time. I will change them out soon, but only because I need to replace a worn suspension strut assembly. Remember my “while were in there” theory of maintenance? Of course they need to be changed in pairs, but why have new shocks only on the front end? What about balance? My mechanics love my theory! Well, so far all I’ve talked about are mechanical suspension systems and it may sound like you need to keep the weight even over the tire patches in all situations. Au contraire! While you want the car’s systems to be relatively stable, balanced and predictable, you the driver need to manage the amount of load on the tire patches using the brakes, throttle and steering wheel to wring the greatest performance from your Porsche. For discussion purposes -- at equilibrium -- that is, not accelerating, decelerating or turning, think of the tire patches as essentially equal and stable in size. Of course, there is a difference between the size of the front and rear patches based on tire width and front-to-rear weight ratio for rear, front and mid-engine cars. (A side thought: How many other auto manufacturers have built modern rear, front and mid-engine cars?) Okay, what happens during braking? The load shifts forward increasing the weight on the front wheels and increasing the size of the front contact patches. Under acceleration the opposite occurs with the weight shift to the rear (love to see those 911’s/930’s squat) loading the rear tires and enlarging the contact patches thus providing more grip. In a constant velocity right turn or left turn the left side and right side patches, respectively, would become larger. Consider braking or accelerating during turning and you might envision a slightly different tire patch footprint for each wheel. Of course modern suspensions do a pretty good job of balancing these loads, but if you’ve aggressively driven an older car with a “soft” suspension, you’ve experienced disconcerting body sway and unequal loading. Okay, so how do you make this contact patch knowledge work for you? Well, now that we understand the suspension’s contribution we need to focus on that loose nut behind the wheel. It stands to reason that abrupt control movements will decrease the stability of the vehicle by “tossing” the weight around. For example, when do you need more grip from the front tires? When turning, so you may ease off the throttle or lightly touch the brakes to “set” the car weight forward before entering a turn. It can be a fairly subtle maneuver. (You can also “trail brake” but that is the subject for another article.) When accelerating out of the turn, if the back end gets “loose,” i.e., slides to the outside of the turn (oversteer), what do you do? A green driver will get off the throttle abruptly (been there, done that) or hard on the brake, which will shift the weight and grip forward when you really need it at the rear. What happens next? Right, a spin! While it seems counterintuitive (that means scary to do), applying some throttle will weight the rear wheels and contact patches and if you are not too far gone and have enough track left, allow you to drive out of the slide. That is the purpose of skid pad practice where one drives in a circle, increasing speed and learning to control the car with throttle to keep moving forward. The Bondurant School does an excellent job of teaching this method of car control. While it is easier to do on the wide open skid pad, it is sometimes scary to apply the technique at speed on a road course. When you feel the back end coming out the intuitive reaction is: “I’m going too fast -- slow down, quickly.” So build up your skill and confidence slowly while expanding your comfort zone by carrying more speed through the turn and using the brakes very sparingly. And remember should you err: “When in a spin – both feet in!” Don’t try to over-control and “save it” which may result in a counter-spin eating up more safety space and putting you further out of control. Just put the brake and clutch to the floor and ride it out. The car will tend to spin in the direction it was going. As Cedric the Entertainer says to his soggy girlfriend in those beer commercials: “It ain’t so bad!” How smoothly you move the steering wheel also contributes to increasing your speed. You are familiar with the terms “understeer” or “push” when the front wheels are turned and the car continues moving straight ahead. In that case you are scrubbing off speed. Many years ago when brakes were far less efficient than today some drivers would “saw” (move back and forth rapidly) the steering wheel before entering a turn to help scrub off speed. Better to be slightly slower and smoother in the turn creating the minimum front tire sideslip or friction. When accelerating out of a turn you should gradually “unwind” the wheel allowing the car to drift out to the edge of the track instead of holding the wheel into the turn and exiting in the middle of the track. One of the reasons instructors advise students to “use the whole track” is so they can keep the speed and momentum up by keeping the front wheels relatively straight ahead. Okay, so how do we put this all together? What does “slow down to go fast” really mean? Generally speaking, the more smoothly you accelerate, brake and turn while maximizing your speed and minimizing unnecessary friction or contact patch sideslip the better your times. Remember, smoothly doesn’t necessarily mean slowly. You need to be quick and smooth. Of course, I haven’t talked about the critical importance of driving the best line, but that, too, is the subject of another article. A smooth, fast lap in autocross is not as flashy, nor does it usually “feel” as fast to the driver as a smooth, controlled lap. In addition to being a little slower to learn a new course marked with cones, I tend to be kind of hyper at the beginning of an autocross session, don’t follow my own advice, and gradually exert more self-control as the day goes on. That’s why I’ll often log my best time on the very last lap available. It focuses my mind when it is the last chance. So I say to my fellow IS Class drivers (you know who you are, Bob Frith), no I am not sandbagging, I just need to learn to listen to my inner voice of reason earlier. Even though a properly driven fast lap in an autocross may not feel as “fast” or satisfying to the driver from a physical standpoint, the ultimate satisfaction is seeing a lower lap time posted among your competitor’s. That’s why I join that historically overlooked driving instructor, Emperor Caesar Augustus, in recommending you learn to “Make haste slowly!”
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